Capsule for dental restoration material

ABSTRACT

There is provided a capsule for dental restoration material, which can administer to a site to be restored of a patient with a mixture in a good state where air bubbles are not substantially contained, immediately after mixing. In the capsule for dental restoration material for directly administering to a restoration site of a tooth with the mixture prepared by subjecting a dental restoration material comprising two components of definite amounts of previously weighed powder component and liquid component accommodated in a cylindrical mixing compartment in an isolated state from each other to making the liquid component flow into the mixing compartment and mixing the both components, an air-permeable filter that does not pass the powder component therethrough but can ventilate air within the mixing compartment into the outside of the mixing compartment is placed in at least a part of a peripheral wall of the mixing compartment.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a capsule for dental restorationmaterial, which can be administered to a site to be restored of apatient, immediately after mixing a dental restoration materialcomprising two components of definite amounts of previously weighedpowder component and liquid component, for filling, cementing, liningand other applications for restoration of a tooth in the dental remedyfield, and in a good state where the mixture does not substantiallycontain air bubbles.

[0003] 2. Description of the Conventional Art

[0004] In general, a dental restoration material is used for restorationof a tooth, such as filling, cementing and lining. As the dentalrestoration material, a two-component system material comprising apowder component and a liquid component, which are reacted with eachother upon mixing, is usually used. Hitherto, this two-component systemdental restoration material was provided for use after appropriatelyweighing the powder component and the liquid component every time andmixing them with each other. However, in recent years, for the purposesof omitting a weighing operation of the powder component and the liquidcomponent and an operation for accommodating the dental restorationmaterial after mixing into a syringe for administering it to a site tobe restored, there have been developed capsules for dental restorationmaterial, in which definite amounts of the powder component and theliquid component are previously weighed and accommodated in an isolatedstate from each other, the isolated state is released at a desired time,the both components are mixed with each other by mechanical shaking in amixer, and the resulting mixture is extruded and administered directlyto a site to be restored, such as a tooth cavity, through a nozzle.

[0005] For example, in a capsule as disclosed in Japanese PatentPublication No. 38853/1991, a powder component of two components isaccommodated in a mixing compartment of a capsule main body, and theother liquid component is charged in a bag (pillow) formed by a sheetfilm, which is assembled in a side portion of the mixing compartmentaccommodating the powder component by means of a clip. The capsule mainbody has an outlet hole in a front end portion thereof. This outlet holecan be clogged in a cylindrical bearing portion in a rear end portion ofa nozzle. Further, the nozzle is kept from the outside by means of aseparately formed cap, thereby preventing the powder component fromleakage out of the mixing compartment. And, at the time of use, the clipis pushed toward a direction of the mixing compartment, thereby smashingand breaking the pillow accommodating the liquid component therein; theliquid component is made flow into an interior of the mixing compartmentthrough an aperture provided on a side wall of the mixing compartment,followed by shaking in a mixer to mix the liquid component and thepowder component with each other; the cylindrical bearing portion in therear end portion of the nozzle is then rotated to release a passage ofthe nozzle; and a plunger is pushed by means of a push rod of aseparately prepared applier to extrude the mixture through the nozzle.

[0006] Further, in a two-component system capsule for mixing anddischarge as disclosed in Japanese Patent Laid-Open No. 268555/1987, apowder component of two components is accommodated in a mixingcompartment within a capsule main body, and the other liquid componentis accommodated in a bag (pillow) formed by a sheet film comprising aresin, a metal foil, or a laminate of a resin and a metal foil. In thispillow, the strength in the main body side is previously set to be low,and the pillow is assembled by a cap to be screw engaged with thecapsule main body in the front end side of the capsule main body. At thetime of use, when the cap is strongly screw engaged with the capsulemain body and moved, the pillow is ruptured, the sheet in the capsulemain body side is broken, and the liquid component flows into the mixingcompartment through an outlet hole provided on a center axis of thefront end of the capsule main body. Thus, when shaking is performed in amixer, the liquid component is mixed with the powder component. Aftermixing, a through rod set within a nozzle provided on a center axis ofthe cap is pushed in and breaks through the sheet of the pillow in thecap side, i.e., in the nozzle side, to form a discharge outlet for themixture. Thereafter, the through rod is removed, a plunger set in aninterior of the rear end portion of the capsule main body is moved intothe side of the front end portion of the capsule main body by a push rodof an applier, and the mixture in the mixing compartment is dischargedthrough the nozzle.

[0007] Further, like Japanese Patent Laid-Open No. 268555/1987 as citedabove, Japanese Patent Publication No. 81384/1991 discloses a capsulefor dental restoration material in which a bag (pillow) having a liquidcomponent accommodated therein, which is formed by a sheet film such asan aluminum foil, is aligned in an outside of a front end of a mixingcompartment of a capsule main body; and the pillow is ruptured by ascrew-in pushing pressure of a cap, thereby making the liquid componentflow into the mixing compartment through an outlet hole on a center axisof the capsule main body. Thus, when shaking is performed in a mixer,the liquid component is mixed with the powder component. After mixing, aplunger having a pillow breakthrough body provided in a rear end portionof the capsule main body is moved by means of a push rod of an applier,to break through a front end of the pillow in the nozzle side, therebyextruding the mixture within the mixing compartment.

[0008] Each of the above-described capsules used a pillow in which theliquid component is wrapped by a sheet film using a metal foil or thelike. As a capsule in a mode not using such a pillow, Japanese PatentLaid-Open No. 131459/1996 discloses a capsule having a structurecomprising a cylindrical capsule main body having a mixing compartmentfor accommodating a powder component therein, in which a thin film-likeseal portion for clogging a circular outlet hole for a mixture, which isprovided on a center axis of a front end portion, is formed, a malescrew is screw provided on an outer periphery side surface from a frontend portion to a center portion, and an applier-engaging groove isengraved on an outer periphery side surface in the vicinity of a rearend portion; a cup-like liquid-accommodating tool for accommodating aliquid component therein, in which a thin film-like seal portion forminga circular flow-in hole for the liquid component is formed on a centeraxis of a front end portion thereof, an evagination portion that isembedded in a cylindrical portion for forming the mixing compartment ofthe capsule main body is provided on an outer periphery surface in thevicinity of the front end portion, and a convex stopper having a sizesuch that it does not easily slide into the capsule main body duringbreaking through the thin film-like seal portion to form the flow-inhole for the liquid component, but, when a large force is applied, it isnot inhibited to slide into the capsule main body, is provided on anouter side surface in the vicinity of a rear end portion thereof; aplunger, in which a tip portion thereof for breaking through the thinfilm-like seal portion of the liquid-accommodating tool and the thinfilm-like seal portion of the capsule main body has a planar rod-likeprotrusion in its front end portion, and an evagination portion that isembedded a cylindrical portion within the liquid-accommodating tool isprovided on an outer side surface in the vicinity of the front endportion; a cap having a nozzle-engaging mouth on a center axis of afront end portion thereof and screw provided, on an inner periphery sidesurface thereof with a female screw to be screw engaged with the malescrew that is screw provided on the capsule main body; and a nozzlehaving a shape such that a rear end portion thereof can be engaged withthe outer surface of the front end portion of the capsule main body.

[0009] In the capsules having such various structures, when the dentalrestoration material comprising two components of definite amounts ofthe previously weighed powder component and liquid component as is mixedby shaking in a mixer, air present in the mixing compartment minglesinto the mixture, whereby it exists as air bubbles. For this reason, thedental restoration material administered in a dental restoration sitesuch as a cavity of a patient contains the air bubbles. Accordingly, thecapsules of the conventional art involved various problems including adecrease in the strength and a change in the color tone with respect tothe dental restoration material.

SUMMARY OF THE INVENTION

[0010] An object of the present invention is to overcome theabove-described problems of the capsules for dental restoration materialof the conventional art and provide a capsule for dental restorationmaterial, which is free from the occurrence of a phenomenon wherein,when a dental restoration material comprising two components of definiteamounts of previously weighed powder component and liquid componentaccommodated in a capsule for dental restoration material of theconventional art is mixed by shaking in a mixer, air present in a mixingcompartment mingles as air bubbles into the mixture.

[0011] In order to achieve the above-described object, we, the presentinventors made extensive and intensive investigations. As a result, ithas been found that in a capsule for dental restoration material fordirectly administering to a restoration site of a tooth with a mixtureprepared by subjecting a dental restoration material comprising twocomponents of definite amounts of previously weighed powder componentand liquid component accommodated in a cylindrical mixing compartment inan isolated state from each other to making the liquid component flowinto the mixing compartment and mixing the both components, when anair-permeable filter that does not pass the powder componenttherethrough but can ventilate air within the mixing compartment intothe outside of the mixing compartment is placed in at least a part of aperipheral wall of the mixing compartment, the capsule for dentalrestoration material is placed in a vacuum atmosphere before mixing thepowder component and the liquid component, whereby the air within themixing compartment can be sucked into the outside of the mixingcompartment, leading to accomplishment of the invention.

[0012] Further, it has also been found that the air-permeable filter maybe placed in at least one of a state where it is placed so as to clog apassage for the mixture, which connects a nozzle for directlyadministering the mixture to the restoration site of the tooth to themixing compartment, a state where it is placed on a side wall of themixing compartment, and a state where it is placed in a plungerextruding the mixture toward the nozzle for directly administering themixture within the mixing compartment to the restoration site of thetooth; and that it is preferred that the air-permeable filter has acharacteristic that an air flow rate is 0.1 to 1,000 L/min·cm² in thecase where the ventilation is carried out under the conditions that apore size is 0.1 to 100 μm, a thickness is 50 to 1,000 μm, and adifferential pressure of air at 25° C. is 69 kPa.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 is an explanatory side cross-sectional view of oneembodiment of a capsule for dental restoration material according to thepresent invention;

[0014]FIG. 2 is an explanatory side cross-sectional view of anotherembodiment of a capsule for dental restoration material according to thepresent invention;

[0015]FIG. 3 is an explanatory side cross-sectional view of a stillanother embodiment of a capsule for dental restoration materialaccording to the present invention; and

[0016]FIG. 4 is an explanatory side cross-sectional view of a stillother embodiment of a capsule for dental restoration material accordingto the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Embodiments of the capsule for dental restoration materialaccording to the present invention will be described in detail withreference to the drawings.

[0018]FIG. 1 is an explanatory side cross-sectional view of oneembodiment of a capsule for dental restoration material according to thepresent invention; FIG. 2 is an explanatory side cross-sectional view ofanother embodiment of a capsule for dental restoration materialaccording to the present invention; FIG. 3 is an explanatory sidecross-sectional view of a still another embodiment of a capsule fordental restoration material according to the present invention; and FIG.4 is an explanatory side cross-sectional view of a still otherembodiment of a capsule for dental restoration material according to thepresent invention.

[0019] In the drawings, a numeral 1 is a monolithically formed syntheticresin-made cylindrical capsule main body, in which a definite amount ofa previously weighed powder component A is accommodated and which isprovided with a cylindrical mixing compartment 1 a for mixing the powdercomponent A with a liquid component B when the liquid component B flowsthereinto. The capsule main body 1 is also provided with an outlet hole1 b for a mixture comprising the powder component A and the liquidcomponent B mixed with each other on a center axis in a front endportion thereof. Each of the embodiments as shown in the drawings has ashape such that a cap 4 provided with a nozzle 4 a as described later onan outer surface of the front end portion, or a cap 4 supporting thenozzle 4 a together with the capsule main body 1, can be fixed (a malescrew in the embodiments shown in FIGS. 1 to 3 and an engagement concavein the embodiment shown in FIG. 4, respectively).

[0020] A numeral 2 is a liquid-accommodating tool for accommodating adefinite amount of the previously weighed liquid component B. In theembodiment shown in FIG. 1, the liquid-accommodating tool 2 is aintegrally formed synthetic resin-made cylindrical cup that can slidetoward the side of the outlet hole 1 b for the mixture within thecylindrical mixing compartment 1 a of the capsule main body 1 and isprovided with a thin film-like seal portion 2 a to form a circularflow-in hole for the liquid component B on a center axis in a front endportion thereof. In the embodiments shown in FIGS. 2 and 3, theliquid-accommodating tool 2 is constituted by a bag (pillow) in whichthe liquid component B is wrapped by a sheet film made by a resin, ametal foil, or a laminate of a resin and a metal foil, to be installedbetween the capsule main body 1 and the cap 4 provided with the nozzle 4a. In the embodiment shown in FIG. 4, the liquid-accommodating tool 2 isconstituted by a bag (pillow) in which the liquid component B is wrappedby a sheet film made by a resin, a metal foil, or a laminate of a resinand a metal foil, to be installed in the outside of an aperture holeprovided on the side surface of the capsule main body 1.

[0021] A numeral 3 is a synthetic resin-made plunger for extruding themixture of the powder component A and the liquid component B mixed witheach other within the mixing compartment 1 a of the capsule main body 1toward the side of the outlet hole 1 b for the mixture. The embodimentshown in FIG. 1 is an embodiment in which the plunger 3 is a integrallyformed synthetic resin-made one that can slide toward the side of thethin film-like seal portion 2 a within the liquid-accommodating tool 2,a rod-like protrusion 3 a breaking through the thin film-like sealportion 2 a of the liquid-accommodating tool 2 is provided in a frontend portion thereof, and after making the liquid component B within theliquid-accommodating tool 2 flow into the mixing compartment 1 a of thecapsule main body 1, the plunger 3 moves together with theliquid-accommodating tool 2, thereby inserting the rod-like protrusion 3a into the outlet hole 1 b for the mixture of the capsule main body 1.The embodiments shown in FIGS. 2 to 4 are an embodiment in which theplunger 3 is a monolithically formed synthetic resin-made one havingsuch a shape that the mixture can slide toward the side of the outlethole 1 b for the mixture within the mixing compartment 1 a of thecapsule main body 1. In the embodiment shown in FIG. 2, the plunger 3 isprovided with the rod-like protrusion 3 a breaking through the sheetfilm in the opposite side to the outlet hole 1 b of theliquid-accommodating tool 2 in the front end portion thereof.

[0022] A numeral 4 is a synthetic resin-made cap having such a shapethat it can be fixed to an outer surface of the front end portion of thecapsule main body 1 for disposing the nozzle 4 a in the front endportion of the capsule main body 1 (a male screw in the embodimentsshown in FIGS. 1 to 3 and an engagement protrusion in the embodimentshown in FIG. 4, respectively). The cap 4 includes the embodiments shownin FIGS. 1 and 4 in which when the cap 4 is fixed to the outer surfaceof the front end portion of the capsule main body 1, it supports thenozzle 4 a between the cap 4 and the capsule main body 1 and those shownin FIGS. 2 and 3 in which the nozzle 4 a is formed monolithically withthe cap 4. Further, there is another embodiment not shown in thedrawings, in which it is not necessary that the liquid-accommodatingtool 2 is disposed facing at the outlet hole 1 b of the capsule mainbody 1, as in the embodiments shown in FIGS. 1 and 4 and in which in thecase where the nozzle 4 a is not rotated, the cap 4 is omitted, wherebythe nozzle 4 a is fixed to the capsule main body 1 by screw engagementor embedding.

[0023] In the case where the liquid-accommodating tool 2 is a capsulecomprising a bag (pillow) containing the liquid component B wrapped bythe sheet film as in the embodiment shown in FIG. 3, a numeral 5 is athrough rod previously set within the nozzle 4 a provided on a centeraxis of the cap 4, such that it breaks through the sheet film in theopposite side to the outlet hole 1 b of the liquid-accommodating tool 2,thereby enabling to supply the mixture of the powder component A and theliquid component B mixed within the mixing compartment 1 a of thecapsule main body 1 into the nozzle 4 a

[0024] In the case where the liquid-accommodating tool 2 is a capsulecomprising a bag (pillow) containing the liquid component B wrapped bythe sheet film as in the embodiment shown in FIG. 4, a numeral 6 is aclip installing the liquid-accommodating tool 2 in an outer portion ofthe side wall of the mixing compartment 1 a of the capsule main body 1.During the use, the clip 6 is pushed toward the direction of the mixingcompartment 1 a to smash and break the sheet film of theliquid-accommodating tool 2 having the liquid component B accommodatedtherein, thereby enabling to supply the liquid component B into themixing compartment 1 a of the capsule main body 1.

[0025] In the capsules for dental restoration material having suchvarious shapes, the capsule for dental restoration material according tothe present invention is characterized by providing an air-permeablefilter 1 c that does not pass the powder component A therethrough butcan ventilate air within the mixing compartment 1 a into the outside ofthe mixing compartment 1 a in at least a part of a peripheral wall ofthe cylindrical mixing compartment 1 a of the capsule main body 1.

[0026] In the embodiment shown in FIG. 1, the air-permeable filter 1 cis placed in a state of clogging a mixture passage connecting the nozzle4 a for directly administering the mixture to a restoration site of atooth to the mixing compartment 1 a; in the embodiments shown in FIGS. 2and 4, the air-permeable filter 1 c is placed on the side wall of themixing compartment 1 a; and in the embodiment shown in FIG. 3, theair-permeable filter 1 c is placed on the side wall of the mixingcompartment 1 a and the plunger 3 extruding the mixture within themixing compartment 1 a toward the nozzle 4 a for directly administeringit to a dental restoration site of a tooth. In order to place theair-permeable filter 1 c in at least a part of the peripheral wall ofthe cylindrical mixing compartment 1 a of the capsule main body 1, it isnecessary to fix the air-permeable filter 1 c along the peripheral wallof the cylindrical mixing compartment 1 a of the capsule main body 1.Accordingly, in other cases than the case where the air-permeable filter1 c is kept between the capsule main body 1 and the cap 4 so as to clogthe outlet hole 1 b of the capsule main body 1 as in the embodimentshown in FIG. 1, an aperture window is formed on the side wall of thecylindrical mixing compartment 1 a of the capsule main body 1 or on theplunger 3 in the side facing at the mixing compartment 1 a, and theair-permeable filter 1 c disposed in this aperture window is pressed andfixed with a presser that is similarly provided with an aperture window.Further, the air-permeable filter 1 c may be provided upon fixing to aninner side wall of the mixing compartment 1 a with an adhesive, etc. Inthis case, it is preferred that the air-permeable filter 1 c is providedin a position other than the inner side wall of the mixing compartment 1a constituting a sliding surface with the plunger 3 (theliquid-accommodating tool 2 in the case of the embodiment shown inFIG. 1) that slides and moves within the mixing compartment 1 a.

[0027] It is preferred that the air-permeable filter 1 c has acharacteristic that an air flow rate is 0.1 to 1,000 L/min·cm² in thecase where the ventilation is carried out under the conditions that apore size is 0.1 to 100 μm, a thickness is 50 to 1,000 μm, and adifferential pressure of air at 25° C. is 69 kPa. This is because thepowder component A accommodated within the cylindrical mixingcompartment 1 a of the capsule main body 1 does not leak out of themixing compartment 1 a during the transportation or keeping; when thecapsule for dental restoration material is installed in acapsule-installing compartment of the mixer and the capsule-installingcompartment is made vacuum, the mixing compartment 1 a can be made to adesired degree of vacuum within a few seconds; and the air-permeablefilter 1 c may be broken through with the rod-like protrusion 3 a of theplunger 3 as in the embodiment shown in FIG. 1.

[0028] Usually, a powder component for dental restoration material has agrain size of 50 μm or less, and a liquid component B for dentalrestoration material has a relatively high viscosity of 220 to 750 cP asmeasured under the temperature condition of 23° C. using a B typerotational viscometer. Accordingly, a material which does not pass thepowder component A therethrough does not inevitably pass the liquidcomponent B therethrough. Examples of materials that can be usedsuitably for the air-permeable filter 1 c having such a characteristic,include fabric materials textured with fibers such as cellulose fibers,glass fibers, polyethylene fluoride fibers, silicone fibers, and silicafibers; and film-like materials made of nylon, polyester, polyethylene,polypropylene, polycarbonate, polyether sulfone, or a mixture thereof.

[0029] Next, a method for use of the capsule for dental restorationmaterial according to the present invention, which comprises theabove-described construction, will be described below.

[0030] First of all, the liquid component B within theliquid-accommodating tool 2 is made flow into the mixing compartment 1 aof the capsule main body 1. In the embodiment shown in FIG. 1, theplunger 3 is made slide toward the side of the outlet hole 1 b of thecapsule main body 1, thereby breaking through the thin film-like sealportion 2 a forming the flow-in hole for the liquid component B providedon the center axis of the front end portion of the liquid-accommodatingtool 2. In the embodiments shown in FIGS. 2 and 3, the capsule main body1 is moved toward the side of the cap 4, thereby rupturing and breakinga portion of the side of the outlet hole 1 b of the sheet filmcomprising a resin, a metal foil, or a laminate of a resin and a metalfoil, of the liquid-accommodating tool 2 installed between the capsulemain body 1 and the cap 4 provided with the nozzle 4 a. In theembodiment shown in FIG. 4, the sheet film comprising a resin, a metalfoil, or a laminate of a resin and a metal foil, of theliquid-accommodating tool 2 installed with the clip in the outside ofthe aperture hole provided on the side surface of the capsule main body1 is ruptured and broken by pushing the clip toward the direction of themixing compartment 1 a.

[0031] Thereafter, this capsule for dental restoration material isinstalled separately in a capsule-installing compartment of an exclusivemixer (not shown); the capsule-installing compartment is made vacuum,thereby sucking air within the mixing compartment 1 a into the outsideof the mixing compartment 1 a via the air-permeable filter 1 c placed inat least a part of the peripheral wall of the cylindrical mixingcompartment 1 a of the capsule main body 1; and the powder component Aand the liquid component B are then mixed with each other by shaking inthe mixer, to obtain a mixture where no air bubbles are present.

[0032] After mixing of the powder component A and the liquid component Bhas been completed, the capsule for dental restoration material is takenout from the mixer and is installed separately in an exclusive applier(not shown), and the plunger 3 is moved toward the side of the outlethole 1 b of the capsule main body 1 by means of a push rod of theapplier. At this time, in the embodiment shown in FIG. 3, a portion inthe opposite side to the outlet hole 1 b of the sheet film comprising aresin, a metal foil, or a laminate of a resin and a metal foil, of theliquid-accommodating tool 2 is broken through by means of the throughrod 5 set within the nozzle 4 a provided on the center axis of the cap4, and the through rod 5 is then taken out from the nozzle 4 a. Further,in the embodiment shown in FIG. 4, the nozzle 4 a is rotated to aposition shown by a broken line, thereby connecting the outlet hole 1 bof the capsule main body 1 to the nozzle 4 a.

[0033] Thus, when the plunger 3 is moved toward the side of the outlethole 1 b of the capsule main body 1 by pushing with the push rod of theapplier, the mixture within the mixing compartment 1 a of the capsulemain body 1 is extruded toward the outlet hole 1 b of the capsule mainbody 1 in a state that no air bubbles are present and administered to arestoration site of a tooth from the nozzle 4 a. In this case, in theembodiment shown in FIG. 1, the rod-like protrusion 3 a of the plunger 3penetrates through the outlet hole 1 b of the capsule main body 1 andbreaks through the air-permeable filter 1 c installed between thecapsule main body 1 and the cap 4 provided with the nozzle 4 a. Further,in the embodiment shown in FIG. 2, when the rod-like protrusion 3 a ofthe plunger 3 penetrates through the outlet hole 1 b of the capsule mainbody 1 and breaks through a portion in the opposite side to the outlethole 1 b of the sheet film comprising a resin, a metal foil, or alaminate of a resin and a metal foil, of the liquid-accommodating tool 2installed between the capsule main body 1 and the cap 4 provided withthe nozzle 4 a, the mixture is administered to a restoration site of atooth from the nozzle 4 a.

[0034] As described above in detail, with respect to the capsule fordental restoration material according to the present invention, in acapsule for dental restoration material for directly administering adental restoration site of a tooth with a mixture prepared by subjectinga dental restoration material comprising two components of definiteamounts of previously weighed powder component and liquid componentaccommodated in a cylindrical mixing compartment in an isolated statefrom each other to making the liquid component flow into the mixingcompartment and mixing the both components, an air-permeable filter thatdoes not pass the powder component therethrough but can ventilate airwithin the mixing compartment into the outside of the mixing compartmentis placed in at least a part of a peripheral wall of the mixingcompartment. Accordingly, when the mixing compartment is made vacuum ina mixer, prior to mixing the dental restoration material comprising twocomponents of definite amounts of the previously weighed powdercomponent and liquid component, and shaking is performed to effectmixing the dental restoration material, the dental restoration materialin a good state that no air bubbles are present in the mixture can beadministered directly to a restoration site such as a cavity of a toothin a simple operation of setting in an applier and extrusion.

[0035] Further, this air-permeable filter may be placed in at least oneof a state where it is placed so as to clog a passage for the mixture,which connects a nozzle for directly administering the mixture to therestoration site of the tooth to the mixing compartment, a state whereit is placed on a side wall of the mixing compartment, and a state whereit is placed in a plunger extruding the mixture toward the nozzle fordirectly administering the mixture within the mixing compartment to therestoration site of the tooth. Accordingly, the air-permeable filter canbe thoroughly applied to various structures of the capsule main body.

[0036] Still further, when the air-permeable filter has a characteristicthat an air flow rate is 0.1 to 1,000 L/min·cm², in the case where theventilation is carried out under the conditions that a pore size is 0.1to 100 μm, a thickness is 50 to 1,000 μm, and a differential pressure ofair at 25° C. is 69 kPa, not only the mixing compartment within thecapsule main body can be easily made vacuum, but also the powdercomponent within the mixing compartment of the capsule main body is freefrom leakage from the air-permeable filter.

[0037] In the light of the above, the capsule for dental restorationmaterial according to the present invention, which possesses variousadvantages, is greatly valuable in contributing to the dental field.

[0038] While the invention has been described in detail and withreference to specific embodiments thereof, it will be apparent to oneskilled in the art that various changes and modifications can be madetherein without departing from the spirit and scope thereof.

What is claimed is:
 1. A capsule for dental restoration material for directly administering to a restoration site of a tooth with a mixture prepared by subjecting a dental restoration material comprising two components of definite amounts of previously weighed powder component and liquid component accommodated in a cylindrical mixing compartment in an isolated state from each other to making the liquid component flow into the mixing compartment and mixing the both components, wherein an air-permeable filter that does not pass the powder component therethrough but can ventilate air within the mixing compartment into the outside of the mixing compartment is placed in at least a part of a peripheral wall of the mixing compartment.
 2. The capsule for dental restoration material as claimed in claim 1 , wherein the air-permeable filter is placed so as to clog a passage for the mixture, which connects a nozzle for directly administering the mixture to the restoration site of the tooth to the mixing compartment.
 3. The capsule for dental restoration material as claimed in claim 1 or 2 , wherein the air-permeable filter is placed on a side wall of the mixing compartment.
 4. The capsule for dental restoration material as claimed in any one of claims 1 to 3 , wherein the air-permeable filter is placed in a plunger extruding the mixture toward the nozzle for directly administering the mixture within the mixing compartment to the restoration site of the tooth.
 5. The capsule for dental restoration material as claimed in any one of claims 1 to 4 , wherein the air-permeable filter has a characteristic that an air flow rate is 0.1 to 1,000 L/min·cm² in the case where the ventilation is carried out under the conditions that a pore size is 0.1 to 100 μm, a thickness is 50 to 1,000 μm, and a differential pressure of air at 25° C. is 69 kPa. 